PCR (polymerase chain reaction) is a relatively new advance (1980's) but it has a great impact in our lives. Specifically, in forensic science, PCR is useful in many sorts of crimes . Up until the PCR method, in order to identify a person forensic scientists would use fingerprints or some other ambiguous methods like teeth marks etc. But now, with PCR, we can compare the genetic material found on a crime scene and compare it with a suspect's genetic material, definitively concluding whether they are the same person or not. The way this works is that we collect a sample from the crime scene with DNA and then PCR amplifies the quantity of DNA in that sample. One of the apparent advantages of this method is that PCR works with even a very small sample, often not even a single cell is required. This makes crime scenes full of information. Hence, succinctly, PCR has helped modern forensic science in that:
1) its results are more definitve than traditional identification methods and subject to less ambiguity
2) it is relatively fast
3) new pieces of evidence can be of value (like some hair cells) and identify the crominal in cases that in older times would be impossible to solve.
Answer:
I think its the first one but I'm not sure
Answer:
D. If an earthworm is given a choice, it will move toward darkness rather than light.
Explanation:
A hypothesis must be a declarative statement that can be tested. That is the only one that follows the guidelines for a good hypothesis.
Answer:
Typically, tortoises live entirely on land, while sea turtles live entirely in the water – they only come on land to lay eggs.
Explanation:
i know a lot about turtles and tortoise
<span>The
answer is allelic frequency. This is also the fraction
of a particular allele of a gene in the population. Allelic
frequency in a population of diploid individuals is calculated using the Hardy Weinberg equation
of p2 + 2pq + q2 = 1. Allelic frequency of all the alleles of the genes must add up to 1 (one).</span>
